Each year, at least one million die from malaria infection. This situation has worsened with the emergence of Plasmodium strains resistant to currently used antimalarials such as chloroquine. With the ever-increasing trend in international travels, there is a greater danger of importing these resistant strains into areas where they never existed before. The long term goal of this project is to obtain information necessary to develop more potent and specific therapeutic agents from plant sources for the treatment of malaria. The antimalarial activity of medicinal herbs: (1). Cymbopogun citratus, (2). Morinda lucida and, (3). Azadirachta indica will be evaluated. The antimalarial activity will be assessed on chloroquine-sensitive and chloroquine-resistant strains of plasmodium falciparum in vitro. [G-3H] hypoxanthine will be used as a radioactive precursor of nucleic acids to assess antimalarial activity by measuring uptake of the precursor into human erythrocytes infected with P. falciparum. First, the crude extracts of the medicinal herbs will be assessed. Then, the active components of the crude extracts will be isolated, purified and assessed on the sensitive p. falciparum strain. This same procedure will be repeated using chloroquine-resistant strain of P. falciparum to assess the potency of the extracts for possible use in the treatment of the chloroquine-resistant strains. The schizonticidal activity of these extracts will also be assessed on P. berqhei berghei in mice.